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$atan2 (aggregation)![](/docs/v5.2/assets/link.svg)
$atan2
New in version 4.2.
Returns the inverse tangent (arc tangent) of
y / x
, wherey
andx
are the first and second values passed to the expression respectively.$atan2
has the following syntax:{ $atan2: [ <expression 1>, <expression 2> ] } $atan2
takes any valid expression that resolves to a number.$atan2
returns values in radians. Use$radiansToDegrees
operator to convert the output value from radians to degrees.By default
$atan2
returns values as adouble
.$atan2
can also return values as a 128-bit decimal as long as the<expression>
resolves to a 128-bit decimal value.For more information on expressions, see Expressions.
Behavior![](/docs/v5.2/assets/link.svg)
null
and NaN
![](/docs/v5.2/assets/link.svg)
If the first argument to $atan2
is null
,
$atan2
returns null
. If the first argument to
$atan2
is NaN
, $atan2
returns NaN
.
If the first argument resolves to a number and the
second argument resolves to either NaN
or null
,
$atan2
returns the NaN
or null
respectively.
Example | Results |
---|---|
or
| NaN |
or
| null |